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Radiometric dating of the Siloam Tunnel, Jerusalem


The historical credibility of texts from the Bible is often debated when compared with Iron Age archaeological finds (refs . 1, 2 and references therein). Modern scientific methods may, in principle, be used to independently date structures that seem to be mentioned in the biblical text, to evaluate its historical authenticity. In reality, however, this approach is extremely difficult because of poor archaeological preservation, uncertainty in identification, scarcity of datable materials, and restricted scientific access into well-identified worship sites. Because of these problems, no well-identified Biblical structure has been radiometrically dated until now. Here we report radiocarbon and U–Th dating of the Siloam Tunnel3,4,5,6,7,8,9,10, proving its Iron Age II date; we conclude that the Biblical text presents an accurate historic record of the Siloam Tunnel's construction. Being one of the longest ancient water tunnels lacking intermediate shafts11,12, dating the Siloam Tunnel is a key to determining where and when this technological breakthrough took place. Siloam Tunnel dating also refutes a claim13 that the tunnel was constructed in the second century bc.

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Figure 1: Location map.
Figure 2: Typical layering in a core drilled at the bottom of the Siloam Tunnel.


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We thank U. Piner (Israel Cave Research Center) for assistance during the initial survey; S. Ashkenazi and Y. Peled (Geological Survey of Israel) for performing the drilling programme; the Research Laboratory for Archaeology and History of Art, Oxford University, for radiocarbon dating; the Open University, Milton Keynes, for 230Th/234U dating; C. Doherty (plaster and mortar) and P. Pettitt (radiocarbon) and Y. Elitzur for discussions, and K. Allred for surveying a new map of the Siloam Tunnel. The National Center for Cooperation Between Science and Archaeology provided financial assistance. Israel Antiquities Authority and Nature and Parks Authority permitted the study.

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Correspondence to Amos Frumkin.

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Frumkin, A., Shimron, A. & Rosenbaum, J. Radiometric dating of the Siloam Tunnel, Jerusalem. Nature 425, 169–171 (2003).

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